Apparatus and method for sorting articles

ABSTRACT

Articles of varying hardness, particularly articles of produce such as dates and the like whose hardness or firmness varies with their moisture content, are sorted by sliding motion of the articles along an inclined ramp or trough having a terminal hump which impels the articles through the air into different sorting receivers according to the hardness of the articles.

United States Patent [191 Jones et al.

[ APPARATUS AND METHOD FOR SORTING ARTICLES [76] Inventors: William B. Jones; William B. Jones,

Jr., both of 10604 Casanes Ave., n? al f- 02,41 v.

[22] Filed: Feb. 12, 1973 [21] Appl. No.: 331,482

[52] US. Cl. 209/115 [51] Int. Cl B07b 13/10 [58] Field of Search 209/1 15-120 [56] References Cited OTHER PUBLICATIONS Sorter for Separating Thin and Thick Walled Ceramic [451 Apr. 23, 1974 Fuse Sleeves, by R. F. Seebode, Western Electric Technical Digest No. 7, July 1967, page 33.

Primary Examiner-M. Henson Wood, Jr. Assistant Examiner-Gene A. Church Attorney, Agent, or Firm-Boniard I. Brown [5 7] ABSTRACT Articles of varying hardness, particularly articles of produce such as dates and the like whose hardness or firmness varies with their moisture content, are sorted by sliding motion of the articles along an inclined ramp or trough having a terminal hump which impels the articles through the air into different sorting receivers according to the hardness of the articles.

11 Claims, 4 Drawing Figures 9'MEN'TEMFR 2 3 I974 APPARATUS AND METHOD FOR SORTING ARTICLES BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates generally to the art of sorting articles of varying hardness according to their degree of hardness and more particularly to a novel article sorting method and apparatus for the purpose described.

2. Discussion of the Prior Art As will become readily evident from the ensuing description, the sorting method and apparatus of the invention may be utilized to sort a variety of articles according to their degree of hardness. One particularly useful application of the invention, however, is sorting dates and other similar articles of produce whose hardness varies with their moisture content. The invention will be described in connection with, but without any intended limitation to, this particular application.

Dates vary substantially in hardness or firmness, depending on their moisture content. The higher the moisture content of a date, the softer will be its consistency. The dates which are suitable for sale in whole form are those which have a relatively high moisture content and hence are relatively soft. Relatively hard dates may be softened by a moisturizing process, such as steaming the dates, or they may be ground up and packaged for sale in their ground up state.

Owing to this varying hardness, it is necessary to sort dates according to their hardness. One common method of accomplishing this is by hand sorting. Such hand sorting, however, is tedious, time-consuming, and hence quite costly.

SUMMARY OF THE INVENTION The presentinvention provides an improved highspeed sorting method and apparatus which is particularly suited to sorting dates according to their hardness or firmness, but may also be used to sort other articles of varying hardness, particularly other articles of produce whose hardness varies with their moisture content.

According to the invention, sorting of articles according to their hardness is accomplished by sliding motion of the articles along an inclined ramp having a terminal hump at its lower end against which the articles impact in such a way that they are launched or impelled through the air along different predetermined trajectories or paths determined by the hardness of the articles. Located along each path is a sorting receiver for catching articles which are launched along the respective path.

The sorting apparatus described is particularly designed for sorting dates or other similar articles of produce whose hardness or firmness varies with their moisture content. This apparatus sorts dates according to hardness or firmness into three classifications, namely soft, mixed, and hard. The soft dates are packaged for sale. The mixed dates, i.e., dates of mixed hardness or firmness, are moisturized as by steaming, to soften them after which they may be re-sorted or packaged. The hard dates may be softened by moisturizing or ground up for sale in ground form.

The described date sorter has a ramp comprising a number of troughs disposed side by side, each with a terminal hump. Dates to be sorted are continuously fed to the upper ends of the troughs by infeed means such as a vibratory table which receives the dates from an infeed conveyor. These troughs are periodically or continuously lubricated, as by spraying a silicone lubricant onto the troughs.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side elevation of a sorting apparatus according to the invention;

FIG. 2 is a fragmentary top plan view of the sorting apparatus;

FIG. 3 is an enlarged section taken on line 3-3 in FIG. 2; and

FIG. 4 is an enlarged section taken on line 4-4 in FIG. 3.

DESCRIPTION OF THE PREFERRED EMBODIMENT The sorting apparatus 10 illustrated in the drawings has an inclined ramp 12 which receives articles 14 to be sorted according to hardness or firmness from an infeed means 16. Located adjacent the lower end of the ramp are hump means 18. The articles 14 are delivered to the upper end of the ramp and slide downwardly along the ramp into impact with the hump means 18. The hump means impels or launches the articles into the air along different predetermined trajectures or paths P P P according to the hardness of the articles. Thus, relatively soft or pliable articles follow the lower path P Relatively hard articles follow the upper path P Articles of intermediate or medium hardness or firmness follow the middle path P Located along these paths are sorting receivers 20, 22, 24 for catching articles moving along their respective paths.

It is important to note here that the articles 14 will not follow the paths P P P precisely. Thus, articles of precisely the same hardness or firmness may not follow precisely the same path. Moreover, each of the three hardness categories mentioned above, i.e., hard, soft, and medium, encompasses a range of hardness or firmness so that articles which fall into the same category may differ in hardness and hence will follow different paths. Accordingly, it should be understood that articles which fall into the same category may be launched from the ramp 12 along any one of a number of paths which together constitute a path range for the respective category. The paths P P P shown represent the medians of the three path ranges for the three hardness categories, i.e., soft, hard, and medium. The sorting receivers 20, 22, 24 are each sized in width to catch articles following any path within the corresponding path range.

As noted earlier, the sorting apparatus of the invention may be utilized to sort a variety of articles according to hardness, but is particularly suited to sorting articles of produce, such as dates and the like, whose hardness varies according to their moisture content.

The particular sorting apparatus 10 shown is a date sorter which will now be described in more detail. The sorting ramp 12 comprises a number of parallel troughs 26 arranged side by side and joined to one another along their longitudinal edges. As shown best in FIG. 3, the upper portion of each trough is straight and inclined at a relatively steep angle. The lower portion of each trough curves forwardly and is indented at its underside to form a rounded hump, previously designated by numeral 18. Referring to F IG. 4, it will be seen that each trough has a metal body 28 of semi-circular cross-section and an anti-friction liner 30 of TEFLON or other suitable anti-friction material.

The upper end of ramp 12 is attached to a frame 32. The lower end of the ramp is supported on the frame by struts 34.

infeed means 16 is mounted on top of the frame 32 and includes an infeed conveyor 36 which receives the articles 14, i.e., dates, to be sorted from a source not shown, and delivers them onto a vibratory table 38. Table 38 is driven in a vibratory motion by a vibrator 40. The front edge of the table extends over the upper end of the ramp 12 in such a way that the vibratory motion of the table causes the incoming dates 14 to roll from the table into the upper ends of the ramp troughs 26. The dates then slide downwardly along the troughs into impact with the humps 18.

As noted earlier, humps l8 impel or launch the articles or dates 14 through the air along the paths P P P according to the hardness or firmness of the dates. Relatively soft dates suitable for immediate packaging and sale, for example, will cushion a substantial portion of the impact energy of the dates against the humps l8 and hence will be launched along the lower path P into the soft date receiver 20. Relatively hard dates, on the other hand, will rebound from the humps with greater energy and hence will follow the higher path P into the hard date receiver 24. Other dates of intermediate or medium hardness will follow the intermediate path P; into the intermediate or mixed date receiver 22.

As already noted, the soft dates which collect in sorting receiver 20 are packaged for sale. The hard dates which collect in receiver 24 may be softened by steaming or they may be ground up for sale in ground form. The dates which collect in the receiver 22 may be resorted or softened by steaming.

The operation of the date sorter 10 is dependent, of course, on proper location and sizing of the sorting receivers 20, 22, 24. It will be understood that these receivers will be positioned and sized to collect dates of their respective hardness category.

If desired, the ramp troughs 26 may be lubricated to effect free sliding motion of the dates 14 along the troughs. The date sorter shown has for this purpose a spray head 42 for periodically or continuously spraying a silicone compound or other lubricant onto the troughs. Improved sorting accuracy may be achieved, if desired, by re-sorting the collected dates from one or more of the sorting receivers 20, 22, 24.

What is claimed as new in support of Letters Patent is: r

l. The method of sorting articles of varying hardness comprising the steps of:

effecting sliding motion of the articles along an inclined ramp with a terminal hump which impels the articles into the air along different predetermined paths according to the hardness of the articles, and

separately collecting the articles following each path.

2. The sorting method of claim 1 wherein: said articles are articles of produce such as dates, whose hardness varies with their moisture content.

3. Apparatus for sorting articles of varying hardness comprising:

an inclined ramp along which said articles are adapted to slide, and

hump means at the lower end of said ramp for impelling the articles into the air along different predetermined paths according to the hardness of the articles.

4. Sorting apparatus according to claim 3 including:

a sorting receiver for catching the articles following each path.

5. Sorting apparatus according to claim 3 wherein:

said ramp comprises a trough.

6. Sorting apparatus according to claim 3 wherein: said ramp comprises a number of parallel troughs disposed side by side, and said hump means comprises a hump at the lower end of each trough. 7. Sorting apparatus according to claim 6 including:

infeed means for delivering articles to the upper ends of said troughs. 8. Sorting apparatus according to claim 3 including:

infeed means for delivering articles to the upper end of said ramp.

9. Sorting apparatus according to claim 3 wherein:

said ramp comprises a number of parallel troughs disposed side by side,

said hump means comprises a hump at the lower end of each trough,

a sorting receiver for catching the articles following each path, and

infeed means for delivering articles to the upper ends of said troughs.

10. Sorting apparatus according to claim 9 including:

means for spraying a lubricant onto said troughs. l l. Sorting apparatus according to claim 3 including:

means for applying a lubricant to said ramp. 

1. The method of sorting articles of varying hardness comprising the steps of: effecting sliding motion of the articles along an inclined ramp with a terminal hump which impels the articles into the air along different predetermined paths according to the hardness of the articles, and separately collecting the articles following each path.
 2. The sorting method of claim 1 wherein: said articles are articles of produce such as dates, whose hardness varies with their moisture content.
 3. Apparatus for sorting articles of varying hardness comprising: an inclined ramp along which said articles are adapted to slide, and hump means at the lower end of said ramp for impelling the articles into the air along different predetermined paths according to the hardness of the articles.
 4. Sorting apparatus according to claim 3 including: a sorting receiver for catching the articles following each path.
 5. Sorting apparatus according to claim 3 wherein: said ramp comprises a trough.
 6. Sorting apparatus according to claim 3 wherein: said ramp comprises a number of parallel troughs disposed side by side, and said hump means comprises a hump at the lower end of each trough.
 7. Sorting apparatus according to claim 6 including: infeed means for delivering articles to the upper ends of said troughs.
 8. Sorting apparatus according to claim 3 including: infeed means for delivering articles to the upper end of said ramp.
 9. Sorting apparatus according to claim 3 wherein: said ramp comprises a number of parallel troughs disposed side by side, said hump means comprises a hump at the lower end of each trough, a sorting receiver for catching the articles following each path, and infeed means for delivering articles to the upper ends of said troughs.
 10. Sorting apparatus accordinG to claim 9 including: means for spraying a lubricant onto said troughs.
 11. Sorting apparatus according to claim 3 including: means for applying a lubricant to said ramp. 